Multitrack recording software programs are also known as sequencers. These names imply their abilities to both record many tracks of audio and MIDI, and to arrange the sections of the song in any sequence or order you wish. They use the standard computer features of cut and paste and give tremendous - and easy - creative control over complex multitrack projects.

Before we get into more details, let's be sure we know the difference between audio and MIDI. Audio is actual sound recordings, plain and simple. MIDI is not. If you are going to record audio only, then a multitrack recording program is all you will probably need. You create the sounds, record them on the tracks, process them as you will and mix them down and you're finished. If you are going to record in MIDI as well, there is another element you will need.

The Bible says that there is nothing new under the sun. This is true, although we give old stuff new names and forms. Consider old-style musicmaking. A pianist, for example, places the music sheet on the piano and plays its. Voila! Beautiful music! That, in a nutshell, is how a MIDI based system works. Let's change the names and see where the old characters are.

The pianist is the sequencer program. It plays the printed music. What is the printed music? The MIDI data. Just as sheet music is only instructions, so is MIDI. It tells which notes to be played, how long to hold them, their dynamics, phrasing and so forth. MIDI adds a few more dimensions, though. Most importantly, it instructs as to which instrument sounds should play which parts. In that regard, MIDI is more like an orchestral score.

The piano itself is replaced by either a bank, a sampler, or a synthesizer. These are all forms of instruments, just as a piano is an instrument. So even though they differ from each other, for now we will call them instruments.

Let's review. The sequencer (pianist) plays the MIDI file (the sheet music) on   the - sound bank, sampler, or synthesizer (the piano). There is nothing new under the sun.

How does the relationship between the sequencer and the instruments work? There are two main variations. One is via what is called a plug in. Plug-ins are sub programs that run with in another program. Some sequencers have plug-in instruments to play the MIDI data and output the music to your sound card and speakers. You choose the instrument for each track, and the sequencer tells the plug-in instruments to play. The most famous of this type of set up are called VST instruments. They are not a stand-alone program, they are simply a set of sounds called upon by the sequencer to play the music.

There are many names for this type of instrument, the clearest one being " sound bank." Sound banks are the most limited of players. They have a fixed set of sounds with little or no ability to be edited. Most sound cards have their own built-in sound bank, so when you play a MIDI file in the sequencer, you can route it to these sounds. VST instruments, and other software sound banks, usually have better quality. As with all products, not all sound banks are created equal.

The other variation of instrument involves a stand-alone sound producing program. An example is the famous " Reason program. To use these, you would run both your sequencer and the sound program simultaneously. The MIDI data will flow from your sequencer to the sound producing program (which will be either a sampler or synthesizer) via a plug-in connecting program. The most common one is called " Rewire," and it does what its name implies. It creates a virtual wire to carry the MIDI data from the sequencer to the sound producing program. In this way the pianist (sequencer) is able to play the piano (the sound producing program). Are you with me?

Here is the difference between a sampler and a synthesizer. Samplers use instrument sounds called " samples." Samples are brief audio recordings of musical instruments. A sample piano, for example, would be recordings of every note on the piano played at different velocities. When you load a piano sample into a sampler and play the MIDI file from your sequencer, you are basically hearing all of those separate recordings of the piano playing back at the appropriate pitch. Samplers allow you to edit each recorded sound, and to record different and new instrument sounds yourself. Their strength lies in providing realistic reproductions of acoustic instruments.

Synthesizers are different - they work on creating artificial sounds. While some sounds may be based on acoustic instruments, synthesizers come into their own by creating amazing atmospheric pads, spacey lead tones and more. By playing with the basic waveforms that make up sound, they can create almost any timbre or texture you desire. A lot of new age music is synthesizer based.

An important thing to realize is that labels aren't always so specific. There are many products out there today that are called " software synthesizers" that are really just sound banks. As with everything, different programs offer different combinations both functions. Some programs, like Reason, contain both sampling and synthesizing functions. Not only that, Reason can play back MIDI files within its own program. On the other hand, some samplers and synthesizers can run as plug-ins from within sequencers. So there is a lot of gray area out there. Nonetheless, these are the main players (no pun intended) in the drama of home music recording in a computer-based studio.